Nebulae….Beautiful Art In The Sky

Nebulae are vast interstellar clouds of gas and dust. They contain mostly hydrogen and helium, but other substances are also present, like relatively huge quantities of alcohol. The word nebula is from Latin, which means “cloud”, named after their hazy appearance on the night sky.
Astronomers have categorized the nebulae (plural of nebula) into three groups, depending on their character. These groups are: Emission nebulae, Reflection nebulae and Planetary nebulae.

Emission nebulae

Emission nebulae are glowing clouds of interstellar gas which have been excited by some nearby energy source, usually a very hot star. The red light seen in many of these pictures is from glowing hydrogen.

Reflection nebula

Reflection nebula is a cloud of gas and dust which does not create its own light, but instead shines by reflecting the light from nearby stars. The brightest reflection nebulae are places where new stars are being formed. Here the gas and dust is thick and shines by the light of new, bright stars.

Planetary nebula

Planetary nebula, often abbreviated as PN or plural PNe, is a kind of emission nebula consisting of an expanding, glowing shell of ionized gas ejected from old red giant stars late in their lives.